---
title: toOneRelationshipKeys
framework: objectivec
role: symbol
role_heading: Instance Property
path: objectivec/nsobject-swift.class/toonerelationshipkeys
---

# toOneRelationshipKeys

The keys for the to-one relationship properties of the receiver, if any.

## Declaration

```swift
var toOneRelationshipKeys: [String] { get }
```

## See Also

### Working with Class Descriptions

- [attributeKeys](objectivec/nsobject-swift.class/attributekeys.md)
- [classDescription](objectivec/nsobject-swift.class/classdescription.md)
- [inverse(forRelationshipKey:)](objectivec/nsobject-swift.class/inverse(forrelationshipkey:).md)
- [toManyRelationshipKeys](objectivec/nsobject-swift.class/tomanyrelationshipkeys.md)